Law enforcement sources tell TMZ federal and local authorities are on the hunt for someone peddling 12 pics of Britney Spears, Jamie Lynn, daughter Maddie and baby daddy Casey Aldridge. One of the pictures shows Jamie Lynn breast feeding Maddie — Jamie Lynn’s left breast is exposed.

The pics were taken on Casey’s digital camera. We’re told he took the camera card to his local Wal-Mart in Louisiana for copies. Law enforcement believes someone at the Wal-Mart may have made extra copies, then tried selling them.

Because Jamie Lynn is a minor, selling the pics — or buying them — could constitute a violation of federal laws prohibiting child pornography. Peddling pictures of a minor’s breast — even if not taken for sexual purposes — could land the seller and the buyer in federal prison if they are marketed across state lines for the purpose of being lurid. Also, anyone purchasing the pics could be prosecuted for the crime of receiving stolen property.